Abstract

The origin of the no‐phonon (NP) luminescence enhancement was explored in Si‐based neighboring confinement structures (NSCs). Post growth annealing was found to lead to quenching of the NP line. Time‐resolved photoluminescence study clarified that the radiative lifetime of the annealed sample increases with increasing temperature, while that of the as‐grown sample shows no significant change at low temperatures (<40 K). These results are reasonably explained by considering that ‘‘in‐plane’’ exciton at the heterointerface is the controlling mechanism for the NP enhancement which is observed at low temperatures in the as‐grown NCS.